The object of the present invention is a simulation device for an electrically controlled braking apparatus (usually called Brake-by-Wire or BBW apparatus).
As is known, in vehicles provided with electrically controlled braking apparatus, the movement that the pedal carries out under the action of the user's foot is used to generate an input signal for the control of the electric motors intended to carry out the braking; the contrast action to the movement on the pedal, which in traditional apparatus is exerted by the fluid pressure, is therefore missing.
The flattening of the pedal would therefore be free, with considerable difficulty by the user in regulating the braking, because the feedback from the pedal towards the user would be missing.
For this reason, it is known to use a braking simulation device which, according to different modes, exerts on the pedal a contrast action to the free flattening of the pedal.
Several solutions of braking simulation devices are known.
According to a first known solution, for example, described in document U.S. Pat. No. 7,357,465, the simulation device is mechanical and is provided with some springs that exert the contrast action on the pedal.
However, the simulation devices of the mechanical type have the drawback of providing a predetermined contrast action, which may not meet the needs of a user, especially if particularly demanding.
According to a further known solution, for example described in document KR 20040079701, the simulation device is electro-mechanical and provides a gear motor and a spring resting on a plate movable by the gear motor, in which the gear motor is in axis with the flattening direction of the pedal and the spring compression. The action of the gear motor, changing the position of the plate, changes the response of the spring and thereby the contrast action exerted thereby.
However, the known solution has the drawback of having to provide for an adequate dimensioning of the motor and of the supports, since it must withstand the maximum load applicable to the pedal.
According to a still further known solution, for example described in document U.S. Pat. No. 6,684,987, the simulation device is of the electric type and includes a gear motor acting on the pedal, arranged with slant axis with respect to the flattening direction of the pedal.
This solution, too, has drawbacks, such as the slow response of the simulation device to the flattening action of the pedal exerted by the user.
The object of the present invention is to provide a simulation device for an electrically controlled braking apparatus (BBW) which overcomes the drawbacks mentioned with reference to the prior art.
Such an object is achieved by a simulation device made according to the following claim 1. The dependent claims describe embodiment variations.